Preheat oven to 350° degrees. Melt butter and pour into the bottom of a 11 x 17 inch baking pan.Pour graham cracker crumbs over butter; pat down. Toss chocolate chips, butterscotch chips, pecans, and coconut together in a large bowl.Spread them out evenly over the graham cracker crust. For the final layer, pour the cans of sweetened condensed milk over the entire top. Bake for 25 to 30 minutes or until top is golden. Cool completely and cut into bars.